(1) Field of the Invention
This invention relates to cleaning foreign matter from lint cotton in a gin.
(2) Description of the Prior Art
In harvesting, seed cotton is stripped or picked from the plant, deposited in a trailer or other vehicle, and transported to a cotton gin. The cotton gin has apparatus for receiving the seed cotton, removing the seeds, cleaning the lint cotton, and pressing the lint into bales for transport to textile mills or compresses for further processing. Cotton gins are ordinarily close to the points of harvest, far from centralized textile mills.
Cotton gins ordinarily do not process lint cotton on a continuous basis. Therefore, the lint cleaner and all other gin equipment must have sufficient capacity to handle peak loads and avoid bottlenecks. A minimum rate for ginning capacity of all gin equipment is about 3,000 pounds of lint cotton per hour. A gin preferably has peak capacity substantially about 4,000 pounds per hour. Historically, the capacity of gins has risen steadily due to improvements in processing methods and equipment.
Prior to our invention, trash or foreign matter in cotton lint presented significant problems to cotton producers. This was especially true of stipper cotton, which contained more bark and leaf trash or foreign matter than picked cotton. For example, in the area of the South Plains of Texas with which we are most familiar, cotton farmers lost an estimated $50,000,000 in 1982 due to price penalties suffered for high trash content in stripper cotton.
Most lint cotton leaving a gin stand will have a minimum of 5% foreign matter content. Although lint cleaners previously employed in cotton gins removed a significant amount of trash, they were almost never able to clean gin lint below 1% foreign matter content, and typically unable to clean gin lint to less than 2% foreign matter content.
Thus, it may be seen that a great need exists for a cotton gin lint cleaner that will satisfactorily clean lint cotton having greater than 5% foreign matter content at rates greater than 4,000 pounds of lint cotton per hour. Although conventional lint cleaners might be arranged in series, or other wise conventionally disposed, to attempt to achieve this goal, experience in the industry has shown that unacceptable fiber damage results.
Applicants are aware of the following United States patents:
SETZER, U.S. Pat. No. 2,014,673
MILLER ET AL, U.S. Pat. No. 2,879,549
GOLDMAN, U.S. Pat. No. 3,081,499
HOLLINGSWORTH, U.S. Pat. No. 3,604,062
WINCH ET AL, U.S. Pat. No. 4,126,914
WINCH ET AL, U.S. Pat. No. 4,219,908
WINCH ET AL '914 discloses a textile mill lint cleaner having a train of rolls with each roll in the train rotating counter to and faster than the preceding roll in the train. The tooth density of each succeeding roll in the train increases substantially over that of the preceding roll. The WINCH ET AL '914 apparatus is disclosed for use in a textile mill, with cards on the rolls having 560 teeth per square inch. WINCH ET AL '914 states at column 10, lines 23-26, that "the treatment unit herein described is capable of producing over 400 pounds and up to 700 pounds or more per hour of a high quality cotton web." This is much less than cotton gin processing requirements of 4,000 pounds or more per hour.
Applicant's believe the Examiner would regard the other patents as pertinent background information.